What is the meaning of だいもん?

大文, 大紋: a type of 直垂 (hitatare) clothing with a family or clan coat of arms displayed prominently

大門: a large gate; a family of high social standing

代紋: a yakuza coat of arms

ダイモン: alternate for ダイモーン (daimōn): a daimon; a tutelary spirit that guides a person; a genius

Source: wiktionary.org